const td = document.querySelectorAll('td')
alert('执行js')
Array.from(td).forEach(item => {
	item.addEventListener('click', () => {
		console.log('点击了')
		Array.from(td).forEach(a => a.classList.remove('active'))
		item.classList.add('active')
	})
});
let i = 0

function loop() {
	let timeid = setTimeout(() => {
		i++
		clearTimeout(timeid)
		loop()
	}, 1);
}
loop()